# STC SA4891NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: ACSS (Aviation Communication and Surveillance Syst, United States
- Description: Installation of Honeywell Vertical Speed Indicator/Traffic Resolution Advisory (VSI/TRA) display.
- Status date: February 28, 2002
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FF7411974F9C530285256CC2000E3F68.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA4891NM

## ADs that name it (0)

None.

## Approved models (6)

- The Boeing Company 727 ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727-100 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727-100C Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727-200 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727-200F Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727C Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))

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